This talk discusses an optical instrument for instantaneous detection of microbes in the environment. The instrument, IMD, has the capability of real time and continuous microbial monitoring. These attributes make the IMD instrument a suitable PAT tool for pharmaceutical manufacturing processes.

The IMD instrument uses elastic light scattering (Mie scattering) to measure the particle size, and inelastic scattering (intrinsic fluorescence) from metabolites inside microbes to differentiate microbes from inert particles. Since the metabolites (e.g. NADH and riboflavin) and other proteins necessary for the generation of this intrinsic fluorescence are present within the cells of microbes, this technique has a broad microbial detection range without the need for sample preparation.

The IMD can be used to detect microbes in the environment in real time and on a continuous basis. We will discuss the potential applications of this technique as a PAT tool for environmental monitoring of pharmaceutical aseptic operations. Some examples of such applications are the timely detection of a microbial excursion during the process and providing trending data for better process understanding.